Hospital patient care generates considerable quantities of infectious medical waste in primary and acute care facilities. There has been a general conversion from reusable, cleanable items, to disposable items over the last three decades. These conversions were made to promote antiseptic techniques in patient care and to decrease the potential for cross-infections between patients, staff and the general public. Recent federal and state government regulations such as the Medical Waste Tracking Act of 1988 and OSHA Medical Facility rules have resulted in a substantial increase in medical waste that must be classified as "infectious."
When a patient is admitted to a hospital, the patient produces approximately 55 pounds of medical waste per day. Approximately 20% of this waste is infectious. The current stated objective of the American Hospital Association and the Centers for Disease Control is to treat medical waste as soon as it is generated. Both organizations recognize that medical waste is primarily an occupational hazard for health care workers and not an environmental problem. The best way to deal with infectious medical waste is to disinfect it at the point of generation and dispose of the treated medical waste with minimum handling and storage on premises.
The need for an effective way to dispose of medical waste has been highlighted by the amendment made to 29 C.F.R. .sctn.1910.1030 which provides for the federal regulation under the Occupational Safety And Health Act, 29 U.S.C. 655, 657 to control bloodborne pathogens. Specifically, the Act calls for the establishment of an exposure control plan, the containment of specimens of blood or other potentially infectious materials and the general tightening of precautionary measures to minimize the spread of disease. A safe and effective way to dispose of hospital waste in the form of soiled garments and apparel would greatly facilitate compliance with the above-referenced Act.
As a result, consumption of medical disposable woven or non-woven products has been growing at a rate of approximately 10% a year. In 1988, sales totaled approximately 1.155 Billion Dollars. It is projected that by 1992, sales of medical disposable non-woven products will reach 1.54 Billion Dollars.
Disposable medical fabrics are generally currently composed of thermoplastic fibers such as polyethylene, polypropylene, polyesters, polyamides and acrylics. These fabrics can also include mixtures of thermoset fibers such as polyamides, polyarimids and cellulosics. They are typically 10-100 grams per square yard in weight and can be woven, knitted or otherwise formed by methods well known to those in the textile arts while the non-wovens can be thermobonded, hydroentangled, wet laid or needle punched and films can be formed by blow or cast extrusion or by solution casting.
Although there is clearly a benefit in the use of disposables in the medical arts by avoiding the necessity of human contact with medical waste which is necessary in the cleaning of comparable reusables, non-biodegradable disposables are posing a problem which is only now being recognized. Landfill sites are becoming increasingly burdened with disposables which do not biodegrade for hundreds of years, if ever. As landfill sites become fully exploited, new sites must be found which are rightfully opposed by residents located proximate to proposed site locations.
It is clear that others have produced useful articles which at least break down or are caused to change their physical confirmation when subjected to hot aqueous solutions. For example, U.S. Pat No. 3,314,809 teaches the production of transparent flexible films from hydroxypropyl cellulose which is taught to be "insoluble in water until the water reaches a temperature of about 60.degree. C." However, hydroxypropyl cellulose, unlike polyvinyl alcohol, does not solubilize in water but simply breaks down forming a cellulose derivative residue.
The prior art has recognized uses for polyvinyl alcohol compositions in the manufacture of water soluble useful articles. For example, U.S. Pat No. 3,413,229 teaches the production of water soluble bags or pouches from which packets or the like are produced containing such materials as detergents, bleaches, insecticides, medicinals, chemicals, dyes, pigments, industrial additives and other materials. It is taught that the contents of the packets are dispersed merely by dropping the packets into water whereupon the bags dissolve and release their contents into aqueous dispersions. However, the referenced patent teaches the production of such films which are both hot and cold water soluble.
Additional references, such as U.S. Pat No. 3,859,125 teach the production of layered articles which include coatings of polyvinyl alcohol. The subject reference teaches coating polyvinyl alcohol on a paper membrane whereby it is taught that the coated paper is soluble in either high or low temperature water. Again, it is incorrect to believe that a cellulose sheet material would be "soluble" in an aqueous solution. At best, cellulose merely disperses. Similarly, U.S. Pat No. 4,343,133 teaches the coating of polyvinyl alcohol onto a non-woven fiber sheet impregnated with latices of polyvinyl acetate in the manufacture of a premoistened towelette which can be disposed of by flushing in plain water without danger of clogging a plumbing system.
There has been the teaching of various medical related products which are generally in the form of articles coated with polyvinyl alcohol employed to enhance disposal. For example, European Patent Application No. 87310534.0 (Publication No. 0272816) teaches the production of an ostomy pouch which can be disposed of in a toilet bowel. The pouch is constructed from laminants of water swellable cold water insoluble films and water-resistant tissue paper. Similarly, U.K. Patent Application No. 2211088 teaches the production of a liner for a bed pan or urine bottle made of polyvinyl alcohol. It is taught that the liner may be disposed of by treatment with water at a temperature above that which it dissolves.
Both U.K. Patent No. 1,187,690 and Japanese Patent No. 72041741 teach the production of stand alone polyvinyl alcohol films which are water soluble. The U.K. patent teaches the production of hospital bags and packing material for such products as detergents and agricultural chemicals while the Japanese patent teaches the use of polyvinyl alcohol films to make laundry bags which dissolve releasing soiled garments contained therein. However, neither reference teaches the unique films of the present invention which can be configured into useful garments and like materials and which are soluble in aqueous solutions only above a threshold value.
It is thus an object of the present invention to provide a method of disposing of garments, linens, drapes, towels and other useful articles after use while avoiding additional burdens being placed upon landfill disposal sites.
It is yet a further object of the present invention to provide a method of disposing of garments, linens, drapes, towels and other useful articles after use such that the garment can be solubilized and medical waste substantially sterilized in a single operation.
These and further objects will be more readily appreciated while considering the following disclosure and appended claims.